Cordless products or devices which use rechargeable batteries are prevalent in the marketplace. Rechargeable batteries may be used in numerous devices ranging from computers to power tools. Since the devices use a plurality of battery cells, the battery cells are commonly packaged in a battery pack. The battery pack may in turn be used to power the devices when coupled thereto. Once depleted, the battery pack may be recharged by a battery charger.
Lithium based battery cells have emerged as the predominant chemistry for such rechargeable batteries. As compared to other battery chemistries, lithium battery cells are lighter and have a larger capacity per unit volume. On the other hand, lithium batteries may deteriorate rapidly when subjected to overcharging, over-discharging, overheating, or other adverse conditions. Therefore, these types of battery system typically employ extensive protective measures to prevent such adverse conditions. Unfortunately, these types of protective measures can also significantly increase product costs.
Therefore, it is desirable to develop a simplified charge and discharge control scheme for use in power tools as well as other types of device that employ rechargeable batteries having similar characteristics. This section provides background information related to the present disclosure which is not necessarily prior art.